Kandras are paid for their contracts using atium, the most valuable metal. For more information, see the last section of the book the Hero of Ages.
Kandra's are used by the main houses as spies against the other houses.
The Mistborn series was written by Brandon Sanderson.
Mistborn: The Final Empire ISBN 076531178X
The Mistborn series by Brandon Sanderson consists of three books in the original trilogy: "Mistborn: The Final Empire," "Mistborn: The Well of Ascension," and "Mistborn: The Hero of Ages." There are also additional books and novellas set in the same world.
Mistborn: The Final Empire 541 pages, in hardback.
They were used for pushing so the mistborn could propel themselves into the air.
A misting is a person who can only burn a single metal. Clubs, Hammond, and Breeze are all mistings. A Mistborn is someone who can burn all metals. Kelsier and Vin are both Mistborn.
The series is still called Mistborn, but the new setting starts with the book The Alloy of Law.
He currently has one in the works set 300 years after the end of the Mistborn Trilogy.
Kelsier
The Lord Ruler
Tindwyl